diff --git a/backend/src/api/mempool-blocks.ts b/backend/src/api/mempool-blocks.ts
index 5d9dcf8f4..6e547e653 100644
--- a/backend/src/api/mempool-blocks.ts
+++ b/backend/src/api/mempool-blocks.ts
@@ -369,7 +369,7 @@ class MempoolBlocks {
     const lastBlockIndex = blocks.length - 1;
     let hasBlockStack = blocks.length >= 8;
     let stackWeight;
-    let feeStatsCalculator: OnlineFeeStatsCalculator | void;
+    let feeStatsCalculator: OnlineFeeStatsCalculator | null = null;
     if (hasBlockStack) {
       if (blockWeights && blockWeights[7] !== null) {
         stackWeight = blockWeights[7];
@@ -380,28 +380,36 @@ class MempoolBlocks {
       feeStatsCalculator = new OnlineFeeStatsCalculator(stackWeight, 0.5, [10, 20, 30, 40, 50, 60, 70, 80, 90]);
     }
 
+    const ancestors: Ancestor[] = [];
+    const descendants: Ancestor[] = [];
+    let ancestor: MempoolTransactionExtended
     for (const cluster of clusters) {
       for (const memberTxid of cluster) {
         const mempoolTx = mempool[memberTxid];
         if (mempoolTx) {
-          const ancestors: Ancestor[] = [];
-          const descendants: Ancestor[] = [];
+          // ugly micro-optimization to avoid allocating new arrays
+          ancestors.length = 0;
+          descendants.length = 0;
           let matched = false;
           cluster.forEach(txid => {
+            ancestor = mempool[txid];
             if (txid === memberTxid) {
               matched = true;
             } else {
-              if (!mempool[txid]) {
+              if (!ancestor) {
                 console.log('txid missing from mempool! ', txid, candidates?.txs[txid]);
+                return;
               }
               const relative = {
                 txid: txid,
-                fee: mempool[txid].fee,
-                weight: (mempool[txid].adjustedVsize * 4),
+                fee: ancestor.fee,
+                weight: (ancestor.adjustedVsize * 4),
               };
               if (matched) {
                 descendants.push(relative);
-                mempoolTx.lastBoosted = Math.max(mempoolTx.lastBoosted || 0, mempool[txid].firstSeen || 0);
+                if (!mempoolTx.lastBoosted || (ancestor.firstSeen && ancestor.firstSeen > mempoolTx.lastBoosted)) {
+                  mempoolTx.lastBoosted = ancestor.firstSeen;
+                }
               } else {
                 ancestors.push(relative);
               }
@@ -410,7 +418,20 @@ class MempoolBlocks {
           if (mempoolTx.ancestors?.length !== ancestors.length || mempoolTx.descendants?.length !== descendants.length) {
             mempoolTx.cpfpDirty = true;
           }
-          Object.assign(mempoolTx, {ancestors, descendants, bestDescendant: null, cpfpChecked: true});
+          // ugly micro-optimization to avoid allocating new arrays or objects
+          if (mempoolTx.ancestors) {
+            mempoolTx.ancestors.length = 0;
+          } else {
+            mempoolTx.ancestors = [];
+          }
+          if (mempoolTx.descendants) {
+            mempoolTx.descendants.length = 0;
+          } else {
+            mempoolTx.descendants = [];
+          }
+          mempoolTx.ancestors.push(...ancestors);
+          mempoolTx.descendants.push(...descendants);
+          mempoolTx.cpfpChecked = true;
         }
       }
     }
@@ -420,7 +441,10 @@ class MempoolBlocks {
     const sizeLimit = (config.MEMPOOL.BLOCK_WEIGHT_UNITS / 4) * 1.2;
     // update this thread's mempool with the results
     let mempoolTx: MempoolTransactionExtended;
-    const mempoolBlocks: MempoolBlockWithTransactions[] = blocks.map((block, blockIndex) => {
+    let acceleration: Acceleration;
+    const mempoolBlocks: MempoolBlockWithTransactions[] = [];
+    for (let blockIndex = 0; blockIndex < blocks.length; blockIndex++) {
+      const block = blocks[blockIndex];
       let totalSize = 0;
       let totalVsize = 0;
       let totalWeight = 0;
@@ -436,7 +460,8 @@ class MempoolBlocks {
         }
       }
 
-      for (const txid of block) {
+      for (let i = 0; i < block.length; i++) {
+        const txid = block[i];
         if (txid) {
           mempoolTx = mempool[txid];
           // save position in projected blocks
@@ -445,30 +470,37 @@ class MempoolBlocks {
             vsize: totalVsize + (mempoolTx.vsize / 2),
           };
 
-          const acceleration = accelerations[txid];
-          if (isAcceleratedBy[txid] || (acceleration && (!accelerationPool || acceleration.pools.includes(accelerationPool)))) {
-            if (!mempoolTx.acceleration) {
-              mempoolTx.cpfpDirty = true;
-            }
-            mempoolTx.acceleration = true;
-            mempoolTx.acceleratedBy = isAcceleratedBy[txid] || acceleration?.pools;
-            mempoolTx.acceleratedAt = acceleration?.added;
-            mempoolTx.feeDelta = acceleration?.feeDelta;
-            for (const ancestor of mempoolTx.ancestors || []) {
-              if (!mempool[ancestor.txid].acceleration) {
-                mempool[ancestor.txid].cpfpDirty = true;
+          if (txid in accelerations) {
+            acceleration = accelerations[txid];
+            if (isAcceleratedBy[txid] || (acceleration && (!accelerationPool || acceleration.pools.includes(accelerationPool)))) {
+              if (!mempoolTx.acceleration) {
+                mempoolTx.cpfpDirty = true;
+              }
+              mempoolTx.acceleration = true;
+              mempoolTx.acceleratedBy = isAcceleratedBy[txid] || acceleration?.pools;
+              mempoolTx.acceleratedAt = acceleration?.added;
+              mempoolTx.feeDelta = acceleration?.feeDelta;
+              for (const ancestor of mempoolTx.ancestors || []) {
+                if (!mempool[ancestor.txid].acceleration) {
+                  mempool[ancestor.txid].cpfpDirty = true;
+                }
+                mempool[ancestor.txid].acceleration = true;
+                mempool[ancestor.txid].acceleratedBy = mempoolTx.acceleratedBy;
+                mempool[ancestor.txid].acceleratedAt = mempoolTx.acceleratedAt;
+                mempool[ancestor.txid].feeDelta = mempoolTx.feeDelta;
+                isAcceleratedBy[ancestor.txid] = mempoolTx.acceleratedBy;
+              }
+            } else {
+              if (mempoolTx.acceleration) {
+                mempoolTx.cpfpDirty = true;
+                delete mempoolTx.acceleration;
               }
-              mempool[ancestor.txid].acceleration = true;
-              mempool[ancestor.txid].acceleratedBy = mempoolTx.acceleratedBy;
-              mempool[ancestor.txid].acceleratedAt = mempoolTx.acceleratedAt;
-              mempool[ancestor.txid].feeDelta = mempoolTx.feeDelta;
-              isAcceleratedBy[ancestor.txid] = mempoolTx.acceleratedBy;
             }
           } else {
             if (mempoolTx.acceleration) {
               mempoolTx.cpfpDirty = true;
+              delete mempoolTx.acceleration;
             }
-            delete mempoolTx.acceleration;
           }
 
           // online calculation of stack-of-blocks fee stats
@@ -486,7 +518,7 @@ class MempoolBlocks {
           }
         }
       }
-      return this.dataToMempoolBlocks(
+      mempoolBlocks[blockIndex] = this.dataToMempoolBlocks(
         block,
         transactions,
         totalSize,
@@ -494,7 +526,7 @@ class MempoolBlocks {
         totalFees,
         (hasBlockStack && blockIndex === lastBlockIndex && feeStatsCalculator) ? feeStatsCalculator.getRawFeeStats() : undefined,
       );
-    });
+    };
 
     if (saveResults) {
       const deltas = this.calculateMempoolDeltas(this.mempoolBlocks, mempoolBlocks);
diff --git a/frontend/src/app/components/accelerate-checkout/accelerate-fee-graph.component.html b/frontend/src/app/components/accelerate-checkout/accelerate-fee-graph.component.html
index a5e258210..564ee0ad1 100644
--- a/frontend/src/app/components/accelerate-checkout/accelerate-fee-graph.component.html
+++ b/frontend/src/app/components/accelerate-checkout/accelerate-fee-graph.component.html
@@ -12,7 +12,7 @@
           </p>
         </div>
         <div class="spacer"></div>
-        <span class="fee">{{ bar.class === 'tx' ? '' : '+' }}{{ bar.fee | number }} <span class="symbol" i18n="shared.sat|sat">sat</span></span>
+        <span class="fee">{{ bar.class === 'tx' ? '' : '+' }}{{ bar.fee | number }} <span class="symbol" i18n="shared.sats">sats</span></span>
         <div class="spacer"></div>
         <div class="spacer"></div>
       </div>
diff --git a/frontend/src/app/components/acceleration-timeline/acceleration-timeline-tooltip.component.html b/frontend/src/app/components/acceleration-timeline/acceleration-timeline-tooltip.component.html
index 07bcdc2f1..0f436f9ac 100644
--- a/frontend/src/app/components/acceleration-timeline/acceleration-timeline-tooltip.component.html
+++ b/frontend/src/app/components/acceleration-timeline/acceleration-timeline-tooltip.component.html
@@ -21,14 +21,14 @@
       </tr>
       <tr *ngIf="accelerationInfo.fee">
         <td class="label" i18n="transaction.fee|Transaction fee">Fee</td>
-        <td class="value">{{ accelerationInfo.fee | number }} <span class="symbol" i18n="shared.sat|sat">sat</span></td>
+        <td class="value">{{ accelerationInfo.fee | number }} <span class="symbol" i18n="shared.sats">sats</span></td>
       </tr>
       <tr *ngIf="accelerationInfo.bidBoost >= 0 || accelerationInfo.feeDelta">
         <td class="label" i18n="transaction.out-of-band-fees">Out-of-band fees</td>
         @if (accelerationInfo.status === 'accelerated') {
-          <td class="value oobFees">{{ accelerationInfo.feeDelta | number }} <span class="symbol" i18n="shared.sat|sat">sat</span></td>
+          <td class="value oobFees">{{ accelerationInfo.feeDelta | number }} <span class="symbol" i18n="shared.sats">sats</span></td>
         } @else {
-          <td class="value oobFees">{{ accelerationInfo.bidBoost | number }} <span class="symbol" i18n="shared.sat|sat">sat</span></td>
+          <td class="value oobFees">{{ accelerationInfo.bidBoost | number }} <span class="symbol" i18n="shared.sats">sats</span></td>
         }
       </tr>
       <tr *ngIf="accelerationInfo.fee && accelerationInfo.weight">
diff --git a/frontend/src/app/components/acceleration/acceleration-fees-graph/acceleration-fees-graph.component.ts b/frontend/src/app/components/acceleration/acceleration-fees-graph/acceleration-fees-graph.component.ts
index d78b663a4..68a2bdd52 100644
--- a/frontend/src/app/components/acceleration/acceleration-fees-graph/acceleration-fees-graph.component.ts
+++ b/frontend/src/app/components/acceleration/acceleration-fees-graph/acceleration-fees-graph.component.ts
@@ -264,7 +264,7 @@ export class AccelerationFeesGraphComponent implements OnInit, OnChanges, OnDest
           type: 'bar',
           barWidth: '90%',
           large: true,
-          barMinHeight: 1,
+          barMinHeight: 3,
         },
       ],
       dataZoom: (this.widget || data.length === 0 )? undefined : [{
diff --git a/frontend/src/app/components/acceleration/accelerations-list/accelerations-list.component.html b/frontend/src/app/components/acceleration/accelerations-list/accelerations-list.component.html
index 8bdd4f14d..ffd8e9c3d 100644
--- a/frontend/src/app/components/acceleration/accelerations-list/accelerations-list.component.html
+++ b/frontend/src/app/components/acceleration/accelerations-list/accelerations-list.component.html
@@ -33,7 +33,7 @@
               <app-fee-rate [fee]="acceleration.effectiveFee" [weight]="acceleration.effectiveVsize * 4"></app-fee-rate>
             </td>
             <td class="bid text-right">
-              {{ (acceleration.feeDelta) | number }} <span class="symbol" i18n="shared.sat|sat">sat</span>
+              {{ (acceleration.feeDelta) | number }} <span class="symbol" i18n="shared.sats">sats</span>
             </td>
             <td class="time text-right">
               <app-time kind="since" [time]="acceleration.added" [fastRender]="true" [showTooltip]="true"></app-time>
@@ -41,7 +41,7 @@
           </ng-container>
           <ng-container *ngIf="!pending">
             <td *ngIf="acceleration.boost != null" class="fee text-right">
-              {{ acceleration.boost | number }} <span class="symbol" i18n="shared.sat|sat">sat</span>
+              {{ acceleration.boost | number }} <span class="symbol" i18n="shared.sats">sats</span>
             </td>
             <td *ngIf="acceleration.boost == null" class="fee text-right">
               ~
diff --git a/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.html b/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.html
index 13d38443e..dbc79fb95 100644
--- a/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.html
+++ b/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.html
@@ -10,10 +10,10 @@
       </td>
       <td class="field-value" [class]="chartPositionLeft ? 'chart-left' : ''">
         <div class="effective-fee-container">
-          @if (accelerationInfo?.acceleratedFeeRate && (!tx.effectiveFeePerVsize || accelerationInfo.acceleratedFeeRate >= tx.effectiveFeePerVsize)) {
+          @if (accelerationInfo?.acceleratedFeeRate && (!effectiveFeeRate || accelerationInfo.acceleratedFeeRate >= effectiveFeeRate)) {
             <app-fee-rate class="oobFees" [fee]="accelerationInfo.acceleratedFeeRate"></app-fee-rate>
           } @else {
-            <app-fee-rate class="oobFees" [fee]="tx.effectiveFeePerVsize"></app-fee-rate>
+            <app-fee-rate class="oobFees" [fee]="effectiveFeeRate"></app-fee-rate>
           }
         </div>
       </td>
diff --git a/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.ts b/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.ts
index f95bb71c8..fb727c1a4 100644
--- a/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.ts
+++ b/frontend/src/app/components/acceleration/active-acceleration-box/active-acceleration-box.component.ts
@@ -1,4 +1,4 @@
-import { Component, ChangeDetectionStrategy, Input, Output, OnChanges, SimpleChanges, EventEmitter } from '@angular/core';
+import { Component, ChangeDetectionStrategy, Input, Output, OnChanges, SimpleChanges, EventEmitter, ChangeDetectorRef } from '@angular/core';
 import { Transaction } from '../../../interfaces/electrs.interface';
 import { Acceleration, SinglePoolStats } from '../../../interfaces/node-api.interface';
 import { EChartsOption, PieSeriesOption } from '../../../graphs/echarts';
@@ -23,7 +23,8 @@ function toRGB({r,g,b}): string {
   changeDetection: ChangeDetectionStrategy.OnPush,
 })
 export class ActiveAccelerationBox implements OnChanges {
-  @Input() tx: Transaction;
+  @Input() acceleratedBy?: number[];
+  @Input() effectiveFeeRate?: number;
   @Input() accelerationInfo: Acceleration;
   @Input() miningStats: MiningStats;
   @Input() pools: number[];
@@ -41,10 +42,12 @@ export class ActiveAccelerationBox implements OnChanges {
   timespan = '';
   chartInstance: any = undefined;
 
-  constructor() {}
+  constructor(
+    private cd: ChangeDetectorRef,
+  ) {}
 
   ngOnChanges(changes: SimpleChanges): void {
-    const pools = this.pools || this.accelerationInfo?.pools || this.tx.acceleratedBy;
+    const pools = this.pools || this.accelerationInfo?.pools || this.acceleratedBy;
     if (pools && this.miningStats) {
       this.prepareChartOptions(pools);
     }
@@ -132,6 +135,7 @@ export class ActiveAccelerationBox implements OnChanges {
         }
       ]
     };
+    this.cd.markForCheck();
   }
 
   onChartInit(ec) {
diff --git a/frontend/src/app/components/amount-selector/amount-selector.component.html b/frontend/src/app/components/amount-selector/amount-selector.component.html
index b509d6fe3..a16a24d4f 100644
--- a/frontend/src/app/components/amount-selector/amount-selector.component.html
+++ b/frontend/src/app/components/amount-selector/amount-selector.component.html
@@ -1,7 +1,7 @@
 <div [formGroup]="amountForm" class="text-small text-center">
     <select formControlName="mode" class="custom-select custom-select-sm form-control-secondary form-control mx-auto" style="width: 70px;" (change)="changeMode()">
         <option value="btc" i18n="shared.btc|BTC">BTC</option>
-        <option value="sats" i18n="shared.sat|sat">sat</option>
+        <option value="sats" i18n="shared.sats">sats</option>
         <option value="fiat" i18n="shared.fiat|Fiat">Fiat</option>
     </select>
 </div>
diff --git a/frontend/src/app/components/block-overview-tooltip/block-overview-tooltip.component.html b/frontend/src/app/components/block-overview-tooltip/block-overview-tooltip.component.html
index f1f5bb3d4..f8fb3c89d 100644
--- a/frontend/src/app/components/block-overview-tooltip/block-overview-tooltip.component.html
+++ b/frontend/src/app/components/block-overview-tooltip/block-overview-tooltip.component.html
@@ -40,7 +40,7 @@
       </tr>
       <tr>
         <td class="label" i18n="transaction.fee|Transaction fee">Fee</td>
-        <td class="value">{{ fee | number }} <span class="symbol" i18n="shared.sat|sat">sat</span> &nbsp; <span class="fiat"><app-fiat [blockConversion]="blockConversion" [value]="fee"></app-fiat></span>
+        <td class="value">{{ fee | number }} <span class="symbol" i18n="shared.sats">sats</span> &nbsp; <span class="fiat"><app-fiat [blockConversion]="blockConversion" [value]="fee"></app-fiat></span>
       </tr>
       <tr>
         <td class="label" i18n="transaction.fee-rate|Transaction fee rate">Fee rate</td>
diff --git a/frontend/src/app/components/rbf-timeline/rbf-timeline-tooltip.component.html b/frontend/src/app/components/rbf-timeline/rbf-timeline-tooltip.component.html
index 46cda0488..19c08bad9 100644
--- a/frontend/src/app/components/rbf-timeline/rbf-timeline-tooltip.component.html
+++ b/frontend/src/app/components/rbf-timeline/rbf-timeline-tooltip.component.html
@@ -19,7 +19,7 @@
       </tr>
       <tr>
         <td class="td-width" i18n="transaction.fee|Transaction fee">Fee</td>
-        <td>{{ rbfInfo.tx.fee | number }} <span class="symbol" i18n="shared.sat|sat">sat</span></td>
+        <td>{{ rbfInfo.tx.fee | number }} <span class="symbol" i18n="shared.sats">sats</span></td>
       </tr>
       <tr *only-vsize>
         <td class="td-width" i18n="transaction.vsize|Transaction Virtual Size">Virtual size</td>
diff --git a/frontend/src/app/components/transaction/transaction-preview.component.html b/frontend/src/app/components/transaction/transaction-preview.component.html
index 63a11a8f0..066e0d442 100644
--- a/frontend/src/app/components/transaction/transaction-preview.component.html
+++ b/frontend/src/app/components/transaction/transaction-preview.component.html
@@ -21,7 +21,7 @@
       </ng-template>
     </span>
     <span class="field col-sm-4 text-center"><ng-container *ngIf="transactionTime > 0">&lrm;{{ transactionTime * 1000 | date:'yyyy-MM-dd HH:mm' }}</ng-container></span>
-    <span class="field col-sm-4 text-right"><span class="label" i18n="transaction.fee|Transaction fee">Fee</span> {{ tx.fee | number }} <span class="symbol" i18n="shared.sat|sat">sat</span></span>
+    <span class="field col-sm-4 text-right"><span class="label" i18n="transaction.fee|Transaction fee">Fee</span> {{ tx.fee | number }} <span class="symbol" i18n="shared.sats">sats</span></span>
   </div>
 
 
diff --git a/frontend/src/app/components/transaction/transaction.component.html b/frontend/src/app/components/transaction/transaction.component.html
index b2e55a3b0..9d3c0d678 100644
--- a/frontend/src/app/components/transaction/transaction.component.html
+++ b/frontend/src/app/components/transaction/transaction.component.html
@@ -606,9 +606,9 @@
   @if (!isLoadingTx) {
     <tr>
       <td class="td-width" i18n="transaction.fee|Transaction fee">Fee</td>
-      <td class="text-wrap">{{ tx.fee | number }} <span class="symbol" i18n="shared.sat|sat">sat</span>
+      <td class="text-wrap">{{ tx.fee | number }} <span class="symbol" i18n="shared.sats">sats</span>
         @if (accelerationInfo?.bidBoost ?? tx.feeDelta > 0) {
-          <span class="oobFees" i18n-ngbTooltip="Acceleration Fees" ngbTooltip="Acceleration fees paid out-of-band"> +{{ accelerationInfo?.bidBoost ?? tx.feeDelta | number }} </span><span class="symbol" i18n="shared.sat|sat">sat</span>
+          <span class="oobFees" i18n-ngbTooltip="Acceleration Fees" ngbTooltip="Acceleration fees paid out-of-band"> +{{ accelerationInfo?.bidBoost ?? tx.feeDelta | number }} </span><span class="symbol" i18n="shared.sats">sats</span>
         }
         <span class="fiat"><app-fiat [blockConversion]="tx.price" [value]="tx.fee + ((accelerationInfo?.bidBoost ?? tx.feeDelta) || 0)"></app-fiat></span>
       </td>
@@ -670,7 +670,7 @@
 <ng-template #acceleratingRow>
   <tr>
     <td rowspan="2" colspan="2" style="padding: 0;">
-      <app-active-acceleration-box [tx]="tx" [accelerationInfo]="accelerationInfo" [miningStats]="miningStats" [hasCpfp]="hasCpfp" (toggleCpfp)="showCpfpDetails = !showCpfpDetails" [chartPositionLeft]="isMobile"></app-active-acceleration-box>
+      <app-active-acceleration-box [acceleratedBy]="tx.acceleratedBy" [effectiveFeeRate]="tx.effectiveFeePerVsize" [accelerationInfo]="accelerationInfo" [miningStats]="miningStats" [hasCpfp]="hasCpfp" (toggleCpfp)="showCpfpDetails = !showCpfpDetails" [chartPositionLeft]="isMobile"></app-active-acceleration-box>
     </td>
   </tr>
   <tr></tr>
diff --git a/frontend/src/app/components/transactions-list/transactions-list.component.html b/frontend/src/app/components/transactions-list/transactions-list.component.html
index 8954e4ecb..9b88678b4 100644
--- a/frontend/src/app/components/transactions-list/transactions-list.component.html
+++ b/frontend/src/app/components/transactions-list/transactions-list.component.html
@@ -321,7 +321,7 @@
       <div class="float-left mt-2-5" *ngIf="!transactionPage && !tx.vin[0].is_coinbase && tx.fee !== -1">
         <app-fee-rate [fee]="tx.fee" [weight]="tx.weight"></app-fee-rate>
         <span class="d-none d-sm-inline-block">&nbsp;&ndash; {{ tx.fee | number }} <span class="symbol"
-            i18n="shared.sat|sat">sat</span> <span class="fiat"><app-fiat [blockConversion]="tx.price" [value]="tx.fee"></app-fiat></span></span>
+            i18n="shared.sats">sats</span> <span class="fiat"><app-fiat [blockConversion]="tx.price" [value]="tx.fee"></app-fiat></span></span>
       </div>
       <div class="float-left mt-2-5 grey-info-text" *ngIf="tx.fee === -1" i18n="transactions-list.load-to-reveal-fee-info">Show more inputs to reveal fee data</div>